Manufacture of extruded metal sections



May 22, 1923.

M. A. HARDY MANUFACTURE OF EXTRUDED METAL SECTIONS FiledlJune .14 1921 Fig-.2.

Patented May 22, 1923.

OFFICE.

MARCEL ADOLPHE HARDY, OF.HEN1\TEBONT, FRANCE.

MANUFACTURE OF EXTRUDED IME'I'AL SECTIONS.

, Applicationfiled June 14, 1921. Serial No. 477,451.

T 0 all whom it may concern:

Be it known that I, MARCEL Anonrnn HARDY, a citizen of the Republic of France, residing at Hennebo-nt, Department of Morb-ihan, France, Chemin du Meunier, have invented a new and useful Improvement in the Manufacture of Extruded Meta-l Sections, of which thefollowing is a specification.

This invention relates to the manufacture of metal sections by the method known as extrusion, which consists in compressing by means of a piston moving in arylindcr, the closed end of which is provided with an opening having the desired cross-sectional profile, a block or mass of metal upon the frontal surface of which the piston presses.

This method which affords good results with metals or alloys which are malleable in the cold or at relatively low temperatures, has not hitherto been applicable in a practical manner for steel.

The material to be worked must in fact be heated in most cases, and to avoid too rapid cooling of the mass of metal it is necessary to employ a cylinder with heat-resisting walls or to raise the walls of the cylinder to a certain temperature.

When it is a question of working metals malleable at low temperatures, like copper, brass.or the like it is possible to construct these walls in a sufiiciently strong and heatresisting manner to withstand the pressure without distortion and to avoid as faras possible any cooling of the mass. But the same does not apply forsteel, which has to be raised to a ver high temperature in order to be workable, or when the cylinder walls are not at a suflicient temperature the steel cools rapidly along the walls, and the force necessary to compress the metallic mass becomes too great. On the other hand, the temperature to which these walls can be raised is limited by the resistance to deformation which they are required to offer.

The present invention has for object to allow the application of this method of manufacture to steel and other metals, alloys or materials of any kind which require to be worked at high temperature.

The invention consists in arranging the compressing piston in such a way as to compress the metal, not over its entire frontal surface as in the known method, but only over the central portion of this surface, so as to reserve between the piston and the innerwall of the cylinder a mass of metal which acts the part of a heat-resisting and insulating layer for the central part of the block, the latter part thus retaining sufficient plasticity to be able to be worked as required.

There can in this way be utilized a cylinder of which the walls are heated to a temperature which does not affect its qualities of resistance, or even in certain cases a cylinder of which the walls are heated only to a very small extent or not at all.

In order better to explain the subject of the invention, Figure l of the accompanying drawing shows diagrammatically the section of the arrangement employed in the known method, while Figure 2 shows the diagrammatic section of the arrangement in accordance with the present invention.

In Figure 1, a is the cylinder and b the piston which compresses the block of metal 0, bearing over the whole frontal surface m n. In the arangement of Figure 2, on the contrary, the piston 0? acts only upon the central 9 of the block of metal 0, which has part p remained plastic, whereas all the peripheral part has formed in cooling a kind of insulating layer.

Suitable arrangementmust evidently be provided for opening the cylinder in order to alloW of introducing therein the block of metal. to be worked, and of withdrawing therefrom the unused mass of metal when the piston has completed its stroke.

The -method may be applied both to blocks of metal heated up to their working temperature, and to metal blocks still in the pasty condition, when incompletely solidified after having been cast.

It may also be applied, whether the block is composed of a single homogeneous substance or of several parts placed one within the other, of the same or of different materials, heated altogether or separately at the same or at different temperatures.

It may be applied equally'as well to any metal or alloy whatever as to steel, or again to any metallic or other substance requiring to be worked at any temperature higher than the ordinary temperature.

Claims 1. A method of manufacturing extruded metal sections, comprising exerting pressure on a mass of metal to be worked, said pressure being applied on anarea whose diameter is substantially less than that of a container in which the metal is placed; whereby a heat so as to exert its main pressure on a central insulating layer of said metal is formed beportion only of the mass of metal. tween the interior surface of the container In testimony whereof I have signed my and a means for exerting said pressure. name to this specification. is

2. A metal extruding device, comprisin MARCEL ADOLPHE HARDY. a closed container, a mass of workable meta Witnesses: positioned in said container, a compressing Loms CALAGE,

member operable in the container positioned HENRI BARTHELEERCY. 

